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PRESENTED BY
01581
STAB ATLAS
CONTAINING
STARS VISIBLE TO THE NAKED EYE
AND
CLUSTEBS, NEBULAE AND DOUBLE STABS
VISIBLE IN SMALL TELESCOPES
TOGETHER WITH
VARIABLE STARS, RED STARS, CHARACTERISTIC STAR GROUPS
ANCIENT CONSTELLATION" FIGURES
AND AN
EXPLANATORY TEXT
BY
WINSLOW UPTON, A.M.
PROFESSOR OF ASTRONOMY IN BROWN UNIVERSITY
GINN AND COMPANY
BOSTON • NEW YORK • CHICAGO ■ LONDON
ATLANTA • DALLAS • COLUMBUS • SAN FRANCISCO
Copyright, 1896
By WINSLOW UPTON
ALL EIGHTS RESERVED
515.7
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QTTic gl tO cure urn 33re£fl
OINN AND COMPANY- PRO-
PRIETORS ' UOSTUN • U.S.A.
PRE FAC E.
This atlas is designed for teachers and students of Astronomy. Its aim is to supply
maps for those who desire to familiarize themselves with the characteristic star groups, and
also to include the leading objects of interest in the sky, which those possessing small tele-
scopes may wish to examine. As the purpose of the atlas is educational rather than pro-
fessional, it has been constructed in a form which it is hoped will be specially adapted to its
use, and it contains some features and omits others which would find a place in an atlas
for professional use.
The maps are on a large scale and are few in number, with liberal overlaps. Con-
forming with the plan of systematic study outlined in the text there are six maps, — two
circumpolar, and four whose areas cover the region between declination N. 40° and S. 40.°
They are subdivided into four divisions corresponding with the four divisions into which
the sky is divided by the equinoctial and solstitial colures. The projection is stereographic,
chosen chiefly because of the gradual narrowing of the hour circles on the equatorial maps
as the declination increases, and the better correspondence of the equatorial and polar maps
at their marginal overlaps. The six skeleton maps are reduced from the larger ones, and
are designed to give the characteristic stellar figures of each constellation area with greater
prominence than they appear on the larger maps. This is secured by omitting the fainter
stars and the historical figures, and by connecting the stars by guiding lines.
The educational purpose of the atlas has caused the retention of the outlines of the
historical figures, which are usually omitted on professional atlases. They are given in
merest outline and for the older constellations of the northern sky only, because of frequent
allusions to them in literature. Similar figures were supplied by those astronomers of the
eighteenth and nineteenth centuries who completed the system of constellations in the
southern hemisphere, but they were added when the use of the figures was becoming obso-
lete; they are of decidedly inferior character in their subjects, since they include such
mechanical objects as air-pump, clock, telescope, chemical furnace ; and they have no
place in literature. For these reasons they are not reproduced.
The purpose of the atlas required its preparation according to the best astronomical
authorities of to-day. The prevailing usage of modern astronomers has been the criterion
adopted ; where usage varies, a decision was necessary, and it has been made with great
care. The only place where any serious difficulty has arisen has been the proper location
of the boundaries between the constellation areas, in which there is no general agreement.
The epoch of the atlas is 1900, and the star places have all been reduced from various
catalogues to that epoch before charting.
The stars charted are those down to the 6.0 magnitude, thus including those readily
visible to the naked eye. A large number of faint stars rarely visible without a
IV PREFACE.
telescope, and which crowd an atlas, were thus omitted. The authority for the magnitudes
is Harvard Photometry, and its extension to the south pole, vols, xiv, xxiv, and xxxiv
of the Annals of the Astronomical Observatory of Harvard College.
Argelander's Uranometria Nova is the basis of the boundaries between the constella-
tion areas, and also of the outlines of the historical figures. Behrmann's extension of the
constellations to the southern pole on Argelander's plan has been adopted on the large
maps, and Gould's revision, which supersedes Argelander's south of 10° N. declination, for
the smaller maps.
The designations of the stars follow Argelander, Behrmann, Heis, and Gould. The
added letters of Gould are used except where his revision of the areas places a star in
another constellation.
The Milky Way is drawn only approximately, based upon the drawings of Heis and
Gould.
The meanings of the Arabic names of stars are taken from Higgins' Arabic Names
of Stars.
The clusters and nebula? charted were selected from Dreyer's New Catalogue, the
variables from Chandler's Second Catalogue, the colored stars from the list in Chambers'
Astronomy and from the notes in Gould's Uranometria Argentina and other catalogues.
The double stars include those within the limits adopted which are catalogued in Webb's
Celestial Objects, and those mentioned by Gould and others. The authority for the posi-
tions and notes in the table is Crossley, Gledhill, and Wilson's Handbook of Double Stars,
and more recent publications of various observers.
The work has been done independently of other publications, but comparisons have
been made with other atlases and star lists in order to secure freedom from error as far
as possible.
Acknowledgment for advice is due and is gratefully made to several astronomers and
educators who have been consulted, especially to Prof. E. C. Pickering, Prof. C. A. Young,
and Mr. D. W. Hoyt. The reproduction of the outlines of the historical figures is due to
the skill of Mr. N. M. Isham of Brown University and the engravei\s Messrs. Bradley and
Poates.
WINSLOW UPTON.
Brown University, Providence, E. I.,
June, 1896.
EXPLANATORY TEXT.
THE CONSTELLATIONS.
The division of the sky into constellations is the oldest part of the science of
Astronomy. It was begun in prehistoric times by Chaldean and Egyptian astronomers,
and was further developed by the Greeks. The Arabian scholars of the Middle Ages
received the system from the Greeks and handed it down, with a few modifications, to
European astronomers. Many additions and alterations were made by astronomers after
the sixteenth century. To-day the system is still used, but only for purposes of notation,
and it has ceased to be of much importance in the strict science of Astronomy.
The primitive astronomers adopted the pictorial plan of distinguishing the stars.
They selected from the heavens prominent groups of stars, gave to them names derived
from natural objects or from their mythology, and imagined figures to be drawn among
the stars to represent the objects. Thus was formed the ancient system of constellations.
Many of them are mentioned by early writers such as Homer, Hesiod, and Aratus, but our
knowledge of the definite location of the groups to which they allude is derived chiefly
from the star catalogue of the Greek astronomer Ptolemy, who lived in the second century
of the Christian era. This star catalogue 1 contains 1028 stars and is made up of the
brighter stars visible in northern latitudes. It groups the stars into forty-eight constel-
lations, which include 926 of the whole number ; the others are mentioned as unclassified,
and are given as additional to the constellations near which they lie. It is probable that
the early astronomers did not intend to map out the whole sky into constellations, but
simply to select the prominent groups and give them names for convenience in their study.
Astrology furnished the motive for the classification, and the study of the star groups was
directed to the determination, if possible, of the influence which the groups had upon the
earth and its inhabitants. Some prominent stars, as Arcturus, were in the unclassified list
and not in any constellation.
The individual stars were named from their positions in the figures which the
astronomers drew among the stars. The figures themselves have not come down to us,
but in Ptolemy's and in subsequent star catalogues the position of each star is given in
two ways : (1) by its place in the constellation figure, and (2) by the system of longitude
and latitude which the Greeks had adopted. The latter system enables the modern
astronomer to identify the stars, and the former to reproduce the outline of the figure with
partial success, depending upon the character of the figure and upon the number of the
stars in the group. Where the constellation has but few stars, as Cards Minor, which has
but two stars in Ptolemy's catalogue, the reproduction of the traditional figure is very
uncertain. In the sixteenth century, the German astronomer Heinfogel secured the
assistance of the artist Albrecht Durer in reproducing the classic figures, and his highly
embellished drawings formed the basis of the figures given on globes and atlases until the
nineteenth century.2 Present atlases either omit them entirely, or give them in merest
outline because of their historical interest and the frequent allusions to them in literature.
They have ceased to have any use hi modern Astronomy.
The first change in the system of constellations described by Ptolemy was made by
transferring the name of the constellation from the space included within the outlines of
1 Baily's edition in Memoirs R. A. S., vol. xiii. 2 Annales Astronomiques, I, 1878.
2 EXPLANATORY TEXT.
the figure to a larger space in the sky, within which the figure represented by the name
was included. Then new constellations were added in the spaces between the original
groups, with the design of covering the whole sky with constellations. The new constel-
lations were added chiefly by astronomers between the sixteenth and nineteenth centuries,
who worked independently of each other. As a result there was no agreement either in
the new constellations or in the drawing of the boundaries between adjacent areas.
To-day there is still disagreement on both these points ; professional astronomers use
different designations for different parts of the sky, and star atlases are not in harmony
with each other, especially for the constellations in the southern hemisphere.
The ancient system of the constellations, with its subsequent additions, survives in
modern Astronomy simply as a means of subdividing the heavens and of giving names to
the areas thus set apart. As the system has been one of growth, without any distinct
plan except the separation of prominent groups of stars, the resulting areas are of various
sizes and shapes. In a few cases the constellation figures crossed each other ; the best
example of this is the constellation Serpens, which crossed Ophiuchus, the figure repre-
senting the serpent-carrier holding the serpent in his hands. In the modern atlas the area
called Serpens is divided into two portions, the western part, marked Caput, and the
eastern, Cauda, to correspond with the positions of the head and the tail of the serpent,
and the area named Ophiuchus extends between them. In some cases, moreover, the same
star was in more than one figure. Thus the northeastern star in the " Square of Pegasus "
is given in Bayer's Atlas both as 8 Pegasi and also as a Andromeda.
Not only are the constellation areas of various sizes, but there is no law by which the
boundaries between them can be definitely marked. The aim of the compilers of atlases
has been to preserve the relation of the areas to the ancient figures as far as possible.
The lack of concerted action has necessarily resulted in variety of treatment, and the
matter of the position of the boundaries is of such minor importance in modern Astronomy
that little interest has been shown in the various schemes proposed for rectifying the
boundaries. A radical change was suggested by Sir John Herschel in 1841 x ; he advocated
a complete rearrangement of the areas, especially of those in the southern sky, and
proposed that each area be made a quadrilateral bounded by arcs of hour circles and
parallels of declinations. This scheme did not meet with favor, but it was revived in a
modified form by Dr. Gould in 1879,2 for the southern constellations, and their boundaries
were drawn by arcs of hour circles or of other great circles and parallels of declination.
The new system of boundaries was made to depart from the former system at the parallel
10° north declination, and all the areas south of this region were bounded by definite arcs
on the above plan instead of by the irregular lines formerly represented. This system
is coming into extensive use, as it is employed for the designation of variable stars, — the
only growing branch of modern Astronomy in which new star names are needed. The old
areas are, however, still retained by some astronomers in preference to the revised areas,
and stars previously named on the old plan, which under the new plan would require
renaming, are usually mentioned under their earlier names.
In this star atlas the constellation areas are named and their boundaries are defined
according to modern usage ; where usage varies it has been necessary to adopt one in
preference to others. The Uranometry of Argelander, published in 1840, extending from
the north pole to 20° or 30° south declination, has been used within these limits ; and its
extension to the south pole, executed on the same plan by Behrmann in 1874, has been
used for the remainder of the sky. On the smaller maps containing the characteristic star
i Memoirs It. A. S., vol. xii. 2 Urauometria Argentina.
THE CONSTELLATIONS. 3
groups of the constellation areas, the boundaries adopted have been those of Argelander
from the north pole to 10° north declination, and the reformed boundaries of Gould from
that parallel southward.
NAMES OF THE CONSTELLATIONS.
The following table contains the names of the constellations included in this atlas.
They are given in their Latin form, which is almost universally used, with accents to
assist in their pronunciation. The genitive case of the name is also appended, as it is
used in the designations of the brighter stars in each constellation. Other columns contain
the meaning of each word, where it is not a proper name, and the map or maps upon
which it is found. The name of the proposer of the constellation is appended. The letter
P in this column indicates that the constellation was in Ptolemy's catalogue, and therefore
belongs to the list of constellations used by the ancient astronomers. The twelve
constellations ascribed to Bayer were introduced into his atlas from earlier observations.
The origin of Crux and Columba is not definitely known, and some of Hevelius' constel-
lations were in use before his time. The constellation Argo is usually subdivided into four
parts, named Carina, Mollis, Puppis, and Vela. The genitive Argus is often used with
stars designated by Greek letters, but the modern tendency is to use the genitive of the
name of the subdivision in which each star is situated.
Table I. — The Constellations.
No.
r
Name.
Genitive.
Meaning.
Map.
Proposer.
1
Androm'-eda
Androm'-eda?
I, II
P
2
Ant'-lia
Ant'-liae
Air pump
III
Lacaille
3
A'-pus
Ap'-odis
Bird of Paradise
VI
Bayer
4
Aqua'-rius
Aqua'-rii
Water carrier
V
P
5
A'-quila
A'-quila3
Eagle
V
P
6
A'-ra"
A'-rse
Altar
VI
P
—
Ar'-go (Navis)
Ar'-gus
Ship Argo
III, VI
P
7
A'-ries
Ari'-etis
Bam
II
P
8
Auri'-ga
Auri'-ga?
Charioteer
I, II, HI
P
9
Boo'-tes
Boo'-tis
Bear keeper
I, IV
P
10
Cse'4um
Cae'-li
Sculptor's chisel
II, VI
Lacaille
11
Camelopar'-dalis
Camelopar'-dalis
Giraffe
I
Hevelius
12
Can'-cer
Can'-cri
Crab
III
P
13
Ca'-nes Venat'-ici
Ca'-numVenatico'-rum
Hunting dogs
I, IV
Hevelius
14
Ca'-nis Ma'-jor
Ca'-nis Majo'-ris
Greater dog
III
P
15
Ca'-nis Mi'-nor
Ca'-nis Mino'-ris
Lesser dog
III
P
16
Capricor'-nus
Capricor'-ni
Goat
V
P
17
Cari'-na
Cari'-nee
Keel(of ship Argo)
VI
—
18
Cassiope'-ia
Cassiope'-ise
I
P
19
Centau'-rus
Centau'-ri
Centaur
IV, VI
P
20
Ce'-pheus
Ce'-phei
I
P
21
Ce'-tus
Ce'-ti
Whale
II
P
22
Chain ae-leon
Chamseleon'-tis
Chameleon
VI
Bayer
23
Cir'-cinus
Cir'-cini
Pair of compasses
VI
Lacaille
24
Colum'-ba
Colum'-bae
Dove
II, VI
—
25
Co'-ma Bereni'-ces
Co'-mae Bereni'-ces
Berenice's hair
IV
Tycho Brahe
26
Coro'-na Austra'-lis
Coro'-nae Austra'-lis
Southern crown
V, VI
P
27
Coro'-na Borea'-lis
Coro'-nee Borea'-lis
Northern crown
IV
P
28
Cor'-vus
Cor'-vi
Crow
IV
P
29
Cra'-ter
Crate'-ris
Cup
III
P
30
Crux
Cru'-cis
Cross
VI
—
31
Cyg'-nus
Cyg'-ni
Swan
I, v
P
32
Delphi'-nus
Delphi '-ni
Dolphin
V
P
EXPLANATORY TEXT.
No.
Name.
Genitive.
Meaning.
Map.
Proposer.
33
Dora'-do
Dora'-dus
Sword fish
VI
Bayer
34
Dra'-co
Draco'-nis
Dragon
I
P
35
Equu'-leus
Equu'-lei
Little horse
V
P
36
Erid'-anus
Erid'-ani
River Po
II, VI
P
37
For'-nax (ckemica)
Fo'rna'-cis
Furnace
II
Lacaille
38
Gem'-ini
Gemino'-rum
Tw.ins
III
P
39
Grus
Gru'-is
Crane
V, VI
Bayer
40
Her'-cules
Her-culis
I, IV
P
41
Horolo'-gium
Horolo'-gii
Clock
II, VI
Lacaille
42
Hy'-dra
Hy'-drse
Snake
III, IV
P
43
Hy'-drus
Hy'-dri
Watersnake
VI
Bayer
44
In'-dus
In'-di
Indian
VI
Bayer
45
Lacer'-ta
Lacer'-tse
Lizard
I, v
Hevelius
46
Le'-o
Leo'-nis
Lion
III
P
47
Le'-o Mi'-nor
Leo'-nis Mino'-ris
Lesser lion
III
Hevelius
48
Le'-pus
Lep'-oris
Hare
II
P
49
Li '-bra
Li'-brse
Balance
IV
P
50
Lu'-pus
Lu'-pi
Wolf
IV, VI
P
51
Lynx
Lyn'-cis
Lynx
I, III
Hevelius
52
Ly'-ra
Ly'ras
Harp
I, v
P
53
Ma'-lus
Ma'-li
Mast(ofshipArgo)
III
—
54
Men'-sa (Mons Mensse)
Men-sse
Table (mountain)
VI
Lacaille
55
Microsco'-pium
Microsco-pii
Microscope
V
Lacaille
56
Monoc'-eros
Monocero'-tis
Unicorn
III
Hevelius
57
Mus'-ca
Mus'-cse
Fly
VI
Bayer
58
Nor'-ma
Nor '-ma?
Rule
IV, VI
Lacaille
59
Oc'-tans
Octan '-tis
Octant
VI
Lacaille
60
Ophiu'-chus
Ophiu'-clii
Serpent carrier
IV, V
P
61
Ori'-on
Orio'-nis
II, III
P
62
Pa'-vo
Pavo'-nis
Peacock
VI
Bayer
63
Peg'-asus
Peg'-asi
Winged horse
V
P
64
Per'-seus
Per'-sei
I, II
P
65
Phoe'-nix
Phceni'-cis
Phoenix
II, VI
Bayer
66
Pic'-tor (Equuleus Pic-
toris)
Picto'-ris
Painter's easel
VI
Lacaille
67
Pis'-ces
Pis'-cium
Fishes
II, V
P
68
Pis'-cis Austra'-lis
Pis'-cis Austra'-lis
Southern fish
V
P
69
Pup -pis
Pup '-pis
Stern (of ship Argo)
III. VI
—
70
Retic'-ulum
Retic'-uli
Net
VI
Lacaille
71
Sagit'-ta
Sagit'-tse
Arrow
V
P
72
Sagitta'-rius
Sagitta'-rii
Archer
V. VI
P
73
Scor'-pius
Scor'-pii
Scorpion
IV, VI
P
74
Sculp'-tor (Apparatus
Sculptoris)
Sculpto'-ris
Sculptor's appara-
tus
II, V, VI
Lacaille
75
Sen '-turn (Sobiesii)
Scu'-ti
Shield of Sobieski
V
Hevelius
76
Ser'-pens
Serpen'-tis
Serpent
IV, V
P
77
Sex'-tans
Sextan '-tis
Sextant
III
Hevelius
78
Tau'-rus
Tau'-ri
Bull
II
P
79
Telesco'-pium
Telesco'-pii
Telescope
VI
Lacaille
80
Trian'-guluin
Trian'-guli
Triangle
II
P
81
Tiian'-gulumAustra'-le
Trian'-guli Austra'-lis
Southern triangle
VI
Bayer
82
Tuca'-na
Tuca'-na?
Toucan
VI
Bayer
83
Ur'-sa Ma'-jor
Ursa? Majo'-ris
Greater bear
I, III
P
84
Ur'-sa Mi'-nor
Ursa? Miuo'-ris
Lesser bear
I
P
85
Ve'-la
Velo'-rum
Sails (of ship Argo)
III, VI
—
86
Vir'-go
Vir'-ginis
Virgin
IV
P
87
Vo'-lans (Piscis volans)
Volan'-tis
Flying fish
VI
Bayer
88
Vulpec'-ula (cum an-
sere)
Vulpec'-ula?
Fox with goose
V
Hevelius
DESIGNATIONS OF STARS. 5
The above list of constellations includes all which are generally accepted at the
present time. The total number is eighty-five if Argo is considered as one constellation,
or eighty-eight if each of its subdivisions is reckoned as a separate constellation. There
are many other constellations which have been proposed by eminent astronomers and used
to a limited extent.1 Thus Bode added nine constellations, one of which, Machhia Mectrica,
was inserted by Argelander in his supplementary map of the southern heavens. Lacaille
substituted for Mains the name Pyxis (genitive Pyx'-idos) mariner's compass, and this is
extensively used to-day. The constellation Antinous, ascribed to Tycho Brahe, is included
in Aquila; Taurus Poniatotvskii, ascribed to Poczobut, is included in Ophiuchus and Serpens.
The constellation Libra, which is the only one of the twelve zodiacal groups not bearing the
name of an animal as the derivation of the word zodiac implies, is in Ptolemy's catalogue
called Claws (of the Scorpion). Scutum is sometimes called by its Greek equivalent Olypeus.
DESIGNATIONS OF STARS.
Individual stars have been designated by astronomers in several different ways :
1. By their position in the constellation figure. This method is now entirely obsolete.
2. By individual names. The names have come down to us chiefly from classical and
mediaeval times, and are either of Latin form or in a corrupted form of the Arabic desig-
nation of the star in its constellation figure. Very few of the names are now used. The
method is nearly obsolete, surviving in only a few of the brightest stars.
3. By Greek or Roman letters, followed by the name of the constellation in the genitive
case of its Latin form. This method was introduced by Bayer early in the seventeenth
century, who lettered the leading stars in each constellation of the northern heavens, using
the Greek alphabet, and if the number of stars in the constellation exceeded the number of
Greek letters, using Roman letters. The stars were lettered in the order of their bright-
ness as far as the several magnitudes were concerned, but no attempt seems to have been
made to -distinguish between the stars of any given magnitude. Later astronomers have
adopted the same system in constellations not in Bayer's list. Nearly all of the stars readily
visible to the naked eye are designated by letters on this plan, and astronomers prefer this
system to any of the others.
4. By Arabic numbers, followed by the name of the constellation in the genitive case
of its Latin form. This method was introduced by Flamsteed in the seventeenth century,
whose numbers follow the order of the stars in right ascension. Other astronomers used
the same plan. This method is used by astronomers for stars not already lettered on Bayer's
plan. Where both letters and numbers have been given, the letters are preferred.
5. By the current number in any well-known modern star catalogue. This method is
used when the star has neither letter nor number.
6. By the position of the star in the sky, the system corresponding to longitude and
latitude on the earth. On the celestial sphere, right ascension and declination are the terms
employed. This method is used for uncatalogued stars.
The brightest stars have designations in all six of the above ways. Thus the bright
star which is near the northern celestial pole was designated (1) the star at the end of the
tail of the lesser bear, (2) Gjedi, Polaris, Cynosura, Alruccabah, (3) a Ursce Minoris, (4) 1
Ursce Minoris. It might also be referred to under (5) as B. A. C. 360, the current numbei
1 See Chambers' Astronomy, vol. iii, chap, vii, ed. 1890, and Burritt's Geography of the Heavens.
6
EXP L ANA TOR Y TEXT.
in the British Association Catalogue (or by a similar designation in any other catalogue in
which it occurs), and under (6) as in right ascension 1 h. 23 min., declination + 88° 46'.
Of these names, a Ursce Minoris is preferred, but Polaris is still in frequent use ; all the
other designations are obsolete.
The majority of stars readily visible to the naked eye are therefore usually designated
by letter and name of constellation area ; a large number, especially of the fainter ones, are
called by a number with the name of the constellation area ; a few have individual names.
Tbe faintest stars visible without a telescope, and all requiring its aid, are referred to by
their numbers in star catalogues, or by their right ascensions and declinations.
In this atlas, following present usage, the individual stars are designated by a letter
or by a number, if such letter or number is in use. The individual names of stars of the
first magnitude, and of a few others which are extensively used, are also given upon the
maps. In referring to the stars, the letter or number should be used with the genitive
of the name of the constellation given in Table I, as a Herculis, 61 Cygni. The Greek
alphabet is here given.
Greek Alphabet.
a
alpha
V
mi
P
beta
i
xi
V
gamma
0
om'-icron
5
delta
IT
Pi
e
eps'-ilon
P
rho
5
zeta
<T
sigma
•n
eta
T
tau
e
theta
V
u'-psilon
i
iota
4>
phi
K
kappa
X
chi
X
lambda
A>
psi
H-
mu
(i>
o'-mega
INDIVIDUAL STAR NAMES.
Individual names have been given to several hundred of the stars. Some were assigned
by the Chaldean astronomers,1 but the earliest which are still used date from classic times
and are given in their Latin form. The Arabian astronomers added many others, the name
usually describing the position of the star in the constellation figure. Individual names of
the stars are now rarely employed ; only those of the brightest stars survive, and even for
them the designation by letters is usually preferred. In this atlas, the individual names
of stars of the first magnitude are given, with a few others, as Algol, which are in general
use. The following table contains names which are sometimes used, together with the
preferred designation by letter with the name of the constellation, and also the meaning of
the word. The pronunciation of the words derived from the Arabic is a matter of uncer-
tainty because they appear in a corrupted form ; the spelling itself is often variously given.
Thus, Betelgeuse is variously written Betelgnese, Beteigenze, Betelgeux, Betelgeuxe, and is
corrupted from ibt al Jauza.2 Its pronunciation is a matter of personal preference.
1 Epping, Aatronomisches aus Babylon.
2 Higgins, Arabic Names of the Stars.
DESIGNATIONS OF STABS.
Table II. — Individual Star Names.
Name.
Other Designation.
Meaning.
Achernar
a
Eridani
The end of the river
Alcor
g
Ursae Majoris
The near one
Aldebaran
a
Tauri
The follower
Alderamin
a
Cepliei
The arm
Alfard
a
Hydraa
The solitary
Algenib
y
Pegasi
The side
Algol
P
Persei
The monster
Alcaid
V
Ursae Majoris
The chief
Alioth
c
Ursa? Majoris
The tail-sheep
Almach
y
Andromeda?
The bound one
Alphecca
a
Corona Borealis
The broken dish
Alpheratz
a
Andromedae
The horse
Alruccabah
a
Ursas Minoris
The chariot
Altair
a
Aquilae
The bird
Antares
a
Scorpii
Equal to Mars (red color)
Arcturus
a
Bootis
Guardian of the bear
Arided
a
Cygni
The tail piece
Bellatrix
y
Orionis
Female warrior
Betelgeuse
a
Orionis
Armpit of the giant
Canopus
a
Argus
(Proper name — Menelaus' pilot)
Capella
a
Auriga?
A little she-goat
Caph
P
Cassiopeia?
Palm of the hand
Castor
a
Geminorum
(Proper name)
Cynosura
a
Ursae Minoris
Dog's tail
Deneb kaitos
P
Ceti
Tail of the whale
Denebola
P
Leonis
Tail of the lion
Dubhe
a
Ursa? Majoris
She-bear
Fomalhaut
a
Piscis Australis
Mouth of the fish
Hyades
Group in Taurus
From Greek — to rain
Kochab
P
Ursae Minoris
Star
Markab
a
Pegasi
Saddle
Megrez
s
Ursae Majoris
Pump
Menkar
a
Ceti
Nostril
Merak
P
Ursae Majoris
Flank
Mira
0
Ceti
Wonderful
Mirach
p
Andromedae
Loins
Mirfak
a
Persei
Elbow
Mizar
t
Ursae Majoris
A girdle
Phecda
y
Ursae Majoris
Thigh
Pleiades
From Greek — to sail
Alcyone
V
Tauri
-
Asterope
21,
22 Tauri
Atlas
27
Tauri
Celieno
g
Tauri.
Atlas, the nymph Pleione,
Electra
17
Tauri
and their seven
Maia
20
Tauri
daughters
Merope
23
Tauri
Pleione
28
Tauri
Taygeta
19
Tauri
Polaris
a
Ursae Minoris
Pole star
Pollux
P
Geminorum
(Proper name)
Prassepe
Cluster in Cancer
Crib or manger
Procyon
a
Canis Minoris
Precursor dog
Ras-Alhague
a
Ophiuchi
Head of the serpent charmer
Ras-Algethi
a
Herculis
Head of the kneeler
Regulus
a
Leonis
Chief
Rigel
P
Orionis
Foot
Scheat ■
P
Pegasi
Foreleg
Schedar
a
Cassiopeiae
Breast
Sirius
a
Canis Majoris
From Siris — the Nile
Spica
a
Virginis
An ear of wheat
Thuban
a
Draconis
A dragon
Vega
1
a
Lyrae
Falling (eagle)
EXPLANATORY TEXT.
BRIGHTNESS OF THE STARS.
In Ptolemy's catalogue the stars were divided into six classes, according to their
brightness. The word '* magnitude " was used as the equivalent of brightness, and the
first six letters of the Greek alphabet were employed in their order to distinguish the
several classes. The word "magnitude" is still used in this erroneous sense, though
the brightness of a star, as we see it, depends upon its distance and intrinsic light-power as
well as upon its size. Stars visible to the naked eye are still subdivided into six " magni-
tudes/' and the fainter stars revealed by the telescope are similarly grouped into those of
the seventh magnitude, eighth magnitude, etc., by an extension of the same principle.
This rough classification has been made the basis of the more accurate classification
which modern astronomy requires. It was found that the several orders of magnitude
estimated by various astronomers differed by a light ratio very nearly 2h That is, a star
of the third magnitude gives 1\ times as much light as one of the fourth magnitude ; one
of the fourth 2\ times as much light as one of the fifth magnitude, and so on. Modern
photometric researches are made upon the assumption of this constant light ratio (the
adopted ratio is 2.512 or -\/l00)- In this way the modern treatment of the subject of the
brightness of the stars is simply a refinement in method, but with no change of plan from
that followed by the earlier astronomers and their successors. Since the stars are of every
degree of brightness, the gradations are expressed upon a numerical scale, with fractions
of a magnitude expressed decimally. Thus, 61 Cygni, which is near the dividing line
between a star of the fifth and one of the sixth magnitude, is now given as of the 5.6
magnitude.
The modern system of designating the brightness of stars is, then, to express it numer-
ically, upon a scale agreeing in general with the ''magnitudes" of the earlier astronomers.
First magnitude stars are those between 0.5 and 1.5 on the photometric scale, second
magnitude stars are those between 1.5 and 2.5, third magnitude stars those between 2.5
and 3.5, and so on. The only important departure from the earlier system is in the case of
the twenty brightest stars of the sky. The ancients included in the group of stars which
they called those of the first magnitude all the brightest stars, ranging from a Canis
Mqjoris, or Sirius, to a Leonis, or Regulus. But the former is thirteen times as bright as
the latter, and therefore should be in a class nearly three magnitudes brighter. The
first magnitude stars, though few in number, really belong in several classes. The actual
measurement of the amount of light given by the twenty brightest stars shows that eleven
of them are between 0.5 and 1.5 magnitude, and hence of the first magnitude ; that seven
should be placed in the next brighter division, and hence are of the zero magnitude, and
that two belong in a class still brighter. As the scale has run out, the brightness of these
two stars is expressed with a minus sign before it. The following table contains the
list of stars generally known as first magnitude stars, rearranged according to the modern
scale.1
1 Annals Observatory of Harvard College, vol. xviii, no. 1.
STAB SYMBOLS.
9
Table III. — Stars of the First Magnitude, rearranged.
A. Stars brighter thaj
• 0 Magnitude.
C. Stars of 1st M
"agnitude
Name.
Magni-
tude.
Map.
N A H E.
Magni-
tude.
Map.
a Canis Majoris (Struts)
— 1.4
II, III
a Tauri (Aldebaran)
1.0
11
a Argus (Cunopus)
— 0.8
VI
a Oriouis (Betelgeuse)
0.9
II, III
B. Stars of 0 Mj
UJNITUDE.
/3 Geminorum (Pollux)
a Leonis (Regains)
1.2
1.3
III
III
a Eridani (Achemar)
0.4
VI
a Crucis
1.0
VI
a Aurigse (Capella)
0.1
I
a Vii'ginis (Spied)
1.1
IV
(i Orionis (Riget)
0.3
II
/3 Centauri
0.7
VI
a Canis Minoris (Procyori)
0.5
III
a Scorpii (Antares)
1.2
IV
a Bootis (Arcturus)
0.2
IV
a Aquilse (Altair)
0.9
V
a Centauri
0.2
VI
a Cygni (Deneb or Arided)
1.4
I
a Lyrse (Vega)
0.2
IV, V
a Piscis Austv&hs(Fo?nalhaut)
1.3
V
STAR SYMBOLS.
In this star atlas, symbols agreeing with those used by Argelander and others have
been adopted to express the several magnitudes. Stars are charted down to the 6.0 magni-
tude, which includes all readily visible to the naked eye. The largest symbol is used for
the nine stars which are brighter than the first magnitude, the next for tbose of the first
magnitude, that is, 0.5 to 1.5 on the photometric scale, the next symbol for those of the
second magnitude, that is, 1.5 to 2.5 on the photometric scale, and so on. In the smaller
maps the magnitudes are expressed by circles of progressive sizes, as there stated.
STAR CLUSTERS AND NEBULAE.
In this atlas are indicated the star clusters and nebulae which can be seen in small
telescopes. It is not always possible to distinguish between nebulous-appearing objects
which may be true nebulae, that is, of gaseous constitution, and tho'se which are clusters of
separate stars. Sometimes, too, the same object is a cluster and nebula combined. The
atlas has two different symbols, but there is sometimes doubt as to which should be
employed.
The study of nebulae requires, except in a few instances, telescopes whose apertures
are at least twelve inches ; in smaller instruments they appear simply as faint patches of
light.
The following tables contain the principal clusters and nebulae which are charted on
the maps, their right ascensions, declinations, and the maps on which they may be found.
Condensed descriptions, usually following those in Dreyer's Catalogue of Nebula? and
Clusters : are appended. To the list of nebulae are also appended a few notes regarding the
most important ones. The numbers in the first column are those in Dreyer's Cata-
logue, the letters N. G. C. standing for New General Catalogue.
1 Memoirs R. A. 8., vol. xlix.
10
EXPLANATORY TEXT.
Table IV. — Star Clusters.
No.
N. G. C.
Right
Ascension.
Declination.
Map.
Description.
104
01
■ 20 m.
-72° 38'
VI
very bright, very large, globular
129
0
24
59 40
I
very large, stars 9th to 13th magnitude
188
0
35
84 47
I
very large, 150-200 stars
225
0
37
61 15
I
large, stars 9th to 10th magnitude
288
0
48
-27 8
II, V
bright, large, globular
362
0
59
-71 23
VI
very bright, very large, globular
663
1
39
60 44
I
bright, large
752
1
52
37 11
II
exceedingly large, visible to eye as nebulous star
869
2
12
56 41
I
exceedingly large, stars 7th to 14th magnitude
884
2
15
56 39
I
very large, very many stars
1039
2
36
42 21
I, II
bright, very large
1245
3
8
46 52
I, II
quite large, rich in faint stars
1291
3
14
-41 28
II, VI
very bright, quite large, globular
1387
3
33
-35 51
II
very bright, quite large, globular
1399
3
35
-35 47
II
very bright, quite large, globular, easily revolved
1436
3
40
-36 26
II
very bright, globular
1528
4
8
50 59
I
bright, many stars
1787
5
0
-65 59
VI
very large, many stars
1850
5
9
-68 53
VI
very bright, large, globular, easily resolved
1851
5
11
-40 9
II, VI
very bright, very large, globular, easily resolved
1855
5
10
-68 58
VI
very bright, large
1857
5
13
39 14
II
somewhat compressed
1904
5
20
— 24 37
II, III
quite large, very many stars, globular, easily resolved
1912
5
22
35 45
II, III
bright, very large, very many stars
1960
5
29
34 5
II, III
bright, very large, very many stars
2015
5
33
— 69 20
VI
very large, many stars
2027
5
35
— 66 59
VI
very large, stars 9th to 11th magnitude
2034
5
36
— 66 57
VI
very large, many stars
2099
5
46
32 31
II, III
quite compressed, exceedingly large number of stars
2118
5
48
— 69 10
VI
very bright, globular
2164
5
59
-68 31
VI
very bright, globular, easily resolved
2168
6
3
24 21
II, III
very large, many stars
2244
6
27
4 56
II, III
about 12 Monocerotis
2287
6
43
— 20 38
II, III
very large, bright
2301
6
47
0 35
III
large, many stars
2323
6
58
- 8 12
III
very large, many stars
2360
7
13
— 15 27
III
very large, many stars
2422
7
32
— 14 16
III
bright, very large, many stars
2437
7
37
— 14 35
III
very bright, very large, very many stars
2447
7
40
-23 38
III
large, stars 8th to 13th magnitude
2451
7
42
— 37 44
III
exceedingly large, about c Puppis
2477
7
49
-38 17
III
bright, large, many stars
2506
7
55
-10 21
III
quite large, very rich in faint stars
2516
7
57
-60 36
VI
very bright, very large, stars 7th to 13th magnitude
2539
8
6
-12 32
III
very large, many stars
2547
8
8
-48 58
VI
bright, large
2632
8
34
20 20
III
Proesepe in Cancer, visible to the naked eye
2682
8
46
12 11
III
very bright,very large, exceedinglylarge number of stars
2808
9
10
-64 27
VI
very large, very many stars, globular
2932
9
32
— 46 30
VI
exceedingly large, very many stars
3114
9
59
-59 38
VI
exceedingly large, stars 9th to 14th magnitude
3532
11
2
— 58 8
VI
exceedingly large, round
3766
11
32
-61 2
VI
very large, 150-200 stars
4147
12
5
19 6
III, IV
very bright, quite large, globular, easily resolved
475.-,
12
48
-59 48
VI
very large, about k Cruris
5024
13
8
18 42
IV
bright, very compressed, globular
5045
13
10
-62 53
VI
very large, very many stars
5139
13
21
-46 47
VI
exceedingly brilliant, u> Centauri, visible to naked eye
5272
13
38
28 53
IV
very bright, very large, vast number of stars
STAE CLUSTERS AND NEBULJE.
11
No.
N. G. C.
Right
Ascension.
Declination.
Map.
5822
lit- 58m.
-53c
57'
VI
5904
15
13
o
27
IV
5986
15
40
-37
27
IV
6067
16
5
-53
57
VI
6087
16
11
— 57
39
VI
6093
16
11
22
44
IV
6169
16
27
-43
50
IV, VI
6171
16
27
-12
50
IV
6205
16
38
36
39
IV
6218
16
42
— 1
46
IV
6227
16
45
-41
O
IV, VI
6254
16
52
— 3
57
IV
6259
16
54
— 44
31
IV, VI
6266
16
55
— 29
58
IV
6333
17
13
-IS
25
IV
6341
17
14
43
15
I, IV
6402
17
32
— 3
11
IV, V
6444
17
44
— 34
50
IV, V
6475
17
48
-34
47
IV, V
6494
17
51
-19
0
IV, V
6523
17
57
-24
23
IV, V
6568
18
7
-21
37
IV, V
6603
18
13
-IS
27
IV, V
6611
18
13
-13
49
IV, V
6626
18
18
— 24
55
IV, V
6633
18
23
6
29
IV, V
6656
IS
30
-23
59
IV, V
6705
18
46
- 6
23
V
6752
19
o
-60
8
VI
6838
19
49
IS
31
V
6866
20
0
43
43
I, v
6885
20
8
26
10
V
6940
20
30
27
58
V
7078
21
25
11
44
V
7089
21
28
— 1
16
V
7092
21
29
48
0
I
7099
21
35
-23
38
V
7243
22
11
49
23
I
7654
23
20
61
o
O
I
7789
23
52
56
10
I
Description.
very large, many stars
very bright, large, many stars
very bright, large
very bright, very large, very many stars
bright, large, stars 7th to 10th magnitude
very bright, large, globular, easily resolved
about fx. Normal
large, very many stars, easily resolved
very bright, vast number of faint stars
very bright, very large, easily resolved
exceedingly large, very rich in stars
bright, very large, easily resolved
bright, very large, very many stars
very bright, large, globular, easily resolved
bright, large, globular, easily resolved
very bright, very large, globular, easily resolved
bright, very large, very many stars, globular
very large, very many stars
very bright, many stars
bright, very large, many stars
very bright, very large
very large, stars of 10th magnitude
very many stars, visible to naked eye
many stars
very bright, large, easily resolved
many bright stars, visible to naked eye
very bright, very large, very many stars, globular
very bright, large
bright, very large, easily resolved
very large, very many stars
large, very many stars
very bright, very large, stars 6th to 11th magnitude
very bright, very large, very many stars
very bright, very large, easily resolved
bright, very large, easily resolved
very large, stars 7th to 10th magnitude
bright, large, globular
large, bright stars
large, many stars
very large, very many stars
Table V. — Nebulae.
No.
N. G. C.
Right
Ascension.
Declination.
Map.
Description.
55
Oh. 10 m.
— 39° 46'
II, V
very bright, very large, very much elongated
221
0
37
40 19
I, II
exceedingly bright, large, round
224
0
37
40 43
I, II
exceedingly bright, large and elongated
253
0
43
-25 51
II, V
exceedingly bright, large and elongated
598
1
28
30 9
II
very bright, very large, round
613
650
651
936
1
1
1
2
29
36
36
23
-29 55
51 4
51 5
- 1 35
II
I
I
II
very bright, very large, very much elongated
very bright ) , , , , .
. . , , y double nebula
very bright )
very bright, very large
1023
1365
1535
1559
2
3
4
4
34
30 .
10
16
38 38
-36 32
-13 0
— 63 2
II
II
II
VI
very bright, very large and elongated
very bright, very large and elongated
very bright, small, planetary
very bright, very large and elongated
12
EXP LAN A TOR Y TEXT.
No.
Rn
!HT
Declination.
M
ip.
Description.
N. G. C.
Ascension.
1763
41
• 57 ™'
— 66° 34'
VI
very bright, very large
1952
5
28
21 57
II,
Ill
very bright, very large and elongated
1976
5
30
- 5 27
II,
III
great nebula about 0 Ononis
1977
5
30
- 4 54
II,
III
about c Orion is
1978
5
28
— 66 18
VI
very bright, very large, oval
1982
5
31
— 5 20
II,
III
very bright, very large
1990
5
31
- 1 16
II,
III
very large, about £ Ononis
2024
5
37
- 1 54
II,
III
bright, very large
2070
5
39
— 69 9
VI
very bright, very large, looped
2392
7
23
21 7
III
bright, small, round
2403
7
27
65 49
I
quite bright, very large and elongated
2683
8
46
33 48
III
very bright, very large and elongated
2841
9
15
51 24
I
very bright, large and much elongated
2867
9
19
— 57 53
VI
very small, planetary
3031
9
47
69 32
I
exceedingly bright and large
3115
10
0
- 7 14
III
very bright, large and much elongated
3132
10
3
-39 57
III
very bright, very large, oval
3199
10
13
— 57 28
VI
very bright, very large
3242
10
20
-18 8
III
very bright, blue tint, planetary
3372
10
41
-59 9
VI
diffused and branching about -q Carmen (Argus')
3379
10
43
13 6
III
very bright, quite large
3587
11
9
55 34
I
very bright, very large, planetary
3623
11
14
13 38
III
bright, very large
3918
11
45
-56 37
VI
small, round, blue tint, planetary
4254
12
14
14 59
III
IV
bright, large, round, three-branched spiral
425S
12
14
47 52
I
very bright, very large and elongated
4382
12
20
18 45
III
IV
very bright, quite large and round
4565
12
31
26 32
III
IV
bright, very large and elongated
4594
12
35
-11 4
III
IV
very bright, very large and elongated
4595
12
35
28 31
III
IV
very bright, very large and elongated
4631
12
37
33 16
III,
IV
very bright, very large and elongated
4736
12
46
41 40
I, IV
very bright, large
4826
12
52
22 43
IV
very bright, very large and elongated
5128
13
20
-42 30
IV,
VI
very bright, very large and elongated
5194
13
26
47 42
I
great spiral nebula
5236
13
31
-29 21
IV
very bright, very large, three-branched spiral
5367
13
52
— 39 30
IV
very bright, very large and elongated
6210
16
40
23 59
IV
very bright, very small, planetary
6326
17
13
-51 38
VI
bright, small, planetary
6369
17
23
-23 41
IV,
V
bright, small, annular
6514
17
56
— 23 2
IV,
V
very bright, very large, trifid
6523
17
57
-24 23
IV,
V
very bright, very large, in cluster
6543
17
58
66 38
I
very bright, small, planetary
6572
18
7
6 50
IV,
V
very bright, small, planetary
6618
18
15
-16 13
IV,
V
bright, very large, two-hooked
6720
18
50
32 54
IV,
V
bright, quite large, annular
6853
19
55
22 27
V
very bright, very large, double condensation
6905
20
18
19 47
V
bright, small, planetary
6960
20
42
30 21
V
quite bright, large, around k Cygni
7009
20
59
-11 46
V
very bright, small, elliptical
7662
23
21
41 59
I
very bright, small, blue tint, planetary
NOTES TO TABLES IV AND V.
221. Companion nebula to the Great Nebula in Andromeda.
224. The Gkeat Nebula in Andromeda. It is plainly visible to the naked eye, and is the
brightest nebula in the heavens. Tt has a nucleus and dark streaks -which in the photographs are
curved as if indicating a spiral structure.
THE COLORS OF STABS. 13
869, 88-1. These two clusters are visible to the naked eve and are designated h and % Persei,
respectively. They are magnificent clusters when viewed with a low-power eyepiece.
1952. The Crab Nebula. It is so named from its appearance in Lord Rosse's reflector.
1976. The Great Nebula ix Orion. It surrounds 6 Ononis, which is visible t<> the
naked eye as a single star, and in the telescope forms the group of four principal stars and two
fainter ones known as the trapezium. The nebula is the largest in the skv and lias a great rift in
it, and also several extensions of irregular shape. A large number of faint stars are involved in
the nebula.
8372. The Nebula around ?/ Carisle (Argus). This is in a region containing many
stars forming an immense cluster involved in nebulous matter. The star ?; Carina', now of about
seventh magnitude, was of extraordinary brilliancy in 1843, exceeded only by Sirius; it fluctuated
very much in brightness between 1800 and 1870.
5139. This cluster, visible to the naked eye and known as a> Oentauri, is probably the most
magnificent in the sky. It contains several thousand stars.
5194. The Great Spiral Nebula. It was so named by Lord Eosse. It is not very con-
spicuous in small telescopes, and its structure is distinguishable only in the largest instruments.
6205. This cluster, often called the Great Cluster in Hercules, is perhaps the most
magnificent visible to northern observers. It is very densely packed with faint stars.
6514. The Trifid Nebula. It contains several dark rifts, and there is evidence that the
nebula has moved, from the change in position of a star with regard to one of these rifts.
6618. The Horseshoe Nebula. It shows this shape only in large instruments.
6720. The Ring Nebula in Lyra. This is the brightest of the circular nebula? whose
condensation is around the circumference of the nebula instead of at its centre.
6853. The Dumbbell Nebula. It was so called by Lord Rosse from its double condensation.
7009. Sometimes called the Saturn Nebula, from a ring seen within the nebula in large
telescopes.
In addition to the clusters of Table IV, the whole Milky Way abounds in regions in which
the stars are closely compressed, and a telescope with a low-power eyepiece will reveal many bril-
liant star groups. The naked-eye cluster, the Pleiades, also abounds in fainter stars, more than a
thousand having been counted and the photographs showing a nebulous background in addition.
THE COLORS OF STARS.
The stars vary in color from red to blue, according to their physical condition. The
reel stars are in many cases variable. The estimates of color by different observers are
often very conflicting, as they depend not only upon the true color of the star, but also
upon the condition of the atmosphere, the color imperfection of the telescope used, and the
sensitiveness of the observer's eye to differences of tint. Moreover as the star appears as a
mere point of light, the color does not seem as pronounced as the word used to express it
suggests. '
In this atlas, stars of a red color are indicated by the letter i? placed as a subscript to
the letter or number designating the star. If the star has no letter or number the R is
placed in parenthesis. Other colors than red are not indicated. The following table con-
tains the stars which are charted as red. in which the color is especially marked, and also a
few of other colors which are noteworthy.
14
EXP LAN A TOR Y TEXT.
Table VI. — Prominent Colored Stars.
Name.
Right
Ascension.
Declination.
Magni-
tude.
Map.
Color.
8 Andromedse
0 b. 34 m,
30° 19'
3
II, V
Orange
R Sculptoris
1 22
— 33 4
var.
II
Red
a Eridani
1 34
— 57 44
1
VI
Red
y Andromedse
1 58
41 51
2
I. II
Orange
o Ceti
2 14
- 3 26
var.
II
Red at maximum
R Trianguli
2 31
33 50
var.
II
Red
a Ceti
2 57
3 42
3
II
Orange
— Eridani
4 30
- 9 10
6
II
Red
a Tauri
4 30
16 19
1
II
Red
R Doradus
4 36
-62 16
var.
VI
Red
5 Orionis
4 48
2 21
6
II
Orange
R Leporis
4 55
-14 57
var.
II
Very red
£ Aurigae
4 56
40 56
4
I, II
Orange
a Orionis
5 47
7 23
var.
II, III
Red
5 Lyncis
6 18
58 29
6
I
Very red
- Aurigse
6 30
38 31
6
II, III
Very red
fj. Canis Majoris
6 51
- 13 54
5
III
Very red
L2 Puppis
7 10
— 44 29
var.
III, VI
Very red
- Puppis
7 29
-14 18
5
III
Very red
- Mali
9 4
-25 27
5
III
Red
R Leonis
9 42
11 54
var.
III
Red
U Hydree
10 33
-12 52
var.
III
Red
p Argus
10 42
— 48 54
3
VI
Red
- Centauri
12 37
— 48 16
5
VI
Very red
R Hydras
13 22
— 22 32
var.
IV
Red
R Centauri
14 9
— 59 27
var.
VI
Red
a Bootis
14 11
19 42
0
IV
Yellow
- Trianguli Australia
15 5
-69 42
5
VI
Red •
/3 Librae
15 12
-9 1
3
IV
Pale green
<j>1 Lupi
15 16
— 35 54
o
O
IV
Very red
X Herculis
16 0
47 31
var.
I
Red
- Scorpii
16 2
— 26 3
5
IV
Red
a Scorpii
16 23
-26 13
1
IV
Very red
a1 Herculis
17 10
14 31
o
O
IV
Orange
y Draconis
17 54
51 30
2
I
Orange
4 Vulpeculse
19 21
19 37
5
V
Orange
R Cygni
19 34
49 58
var.
I
Red
x c:ygni
19 47
32 40
var.
V
Red
T Cepliei
21 8
68 5
var.
I
Red
ix Cepliei
21 40
58 19
var.
I
Red
8 Andromedse
23 13
48 28
5
I
Red
19 Piscium
23 41
2 56
5
n, V
Red
R Cassiopeise
23 53
50 50
var.
I
Red
30 Piscium
23 57
- 6 34
5
II, V
Red
VARIABLE STABS. 15
VARIABLE STARS.
In this atlas are included variable stars whose brightness at their maximum equals the
sixth magnitude, and also temporary stars which at their brightest were visible to the naked
eye but now require a telescope or are wholly invisible. They are indicated by the letter V
placed as a subscript to the letter or number designating the star ; if the star has no letter
or number the letter V is placed in parenthesis. Variable stars, if not already lettered, are
designated by the later letters of the alphabet, beginning with E, followed by the Latin
genitive of the constellation. They are lettered in the order of their discovery, and after Z
is reached the letters are repeated in pairs, RR, RS, etc.
The star symbol used on the maps corresponds with the maximum brightness, except
in the case of temporary stars now invisible to the naked eye. The folio whig table con-
tains those charted, with notes regarding the changes in brightness which they experience.
The list is made from Chandler's Second Catalogue of Variable Stars.1 The numbers in
the first column are those of that catalogue. Stars of the Algol-type are those which are
usually at their maximum brightness, but which periodically decrease to a minimum and
return again to the maximum.
The variability of the light of stars is of especial interest, because it must be accounted
for in any theory of the physical state of the stars. Slow changes in the amount of light
given out are to be expected, but periodical changes require special explanation. The
greatest interest attaches to stars of the Algol-type, which are most naturally accounted
for by the periodic passing between us and the star of an eclipsing body. That such a body
exists in the case of Algol has been proved by the periodic displacement of the lines in
the spectrum of the star, so that the star and its companion really form a binary, the two
revolving around their common centre of gravity. Another class of variables exhibits the
light change in a manner precisely the reverse of that of the Algol stars, the star remaining
at its minimum brightness the greater part of the time and periodically increasing to a
maximum. The periods are not always the same, nor is the brightness at the successive
maxima uniform, so that the explanation of this type of variability is not simple and is at
present quite conjectural. Another class of variables shows continuous changes in the light,
now increasing and now decreasing, the star not remaining at all at any definite degree of
brightness. The successive maxima and minima and the rates of change are often variable
also, so that the phenomenon is very complicated. Other stars occasionally fluctuate in
brightness, but not in any distinct period which can be determined. Another class of
variables includes the New or Temporary Stars, improperly so called because they are not
new creations, and it is only the great increase of light which is temporary. In every case
the light increases rapidly to a maximum, and decreases more slowly, with fluctuations
that are remarkably irregular and accompanied by changes in the star's spectrum whose
explanation is wholly conjectural.
i The Astronomical Journal, Nos. 300, 347, 369.
16
EXPLANATORY TEXT.
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DOUBLE STABS. 10
DOUBLE STARS.
The double stars in the sky number many thousands. The term is used to include
those stars which are within 30" of each other. The eye cannot separate stars unless the
distance of the stars is very much greater than this, so that a telescope is necessary for the
examination of these objects.
A distinction must be made between naked-eye doubles and telescopic doubles, the
latter only receiving the name Double Stars. The former are two stars whose separation
must be several minutes of arc, as £ Ursce Majoris in the handle of the Dipper, and e Lyrce.
The former is evidently two stars, but the latter is a severe test for the unaided eye, just
as the separation of each of its components into two stars is a good test for a telescope.
The main components of e Lyrce are distant 3', about the smallest angle which «the eye
can distinguish.
A further distinction must be made between Double Stars and Binaries. The former
is a generic term, applying to all stars separated by less than 30". (Some authorities
would adopt even a smaller limit, as 15".) The latter is a specific term, and is limited to
such double stars as are proved to form a system, the two stars revolving about their
common centre of gravity. The aim of the study of double stars is the detection of bin-
aries, which is accomplished by observing the changes in the relative position of the
component stars. The existence of stellar systems is a definite proof of the universality
of attraction, as announced by Newton when he formulated the law of gravitation.
In addition to the binaries ocularly revealed by the telescope are those whose com-
ponents are so near each other that they cannot be distinguished with the telescope.
They have been detected by the periodic doubling of the lines of their spectra, and are
known as spectroscopic binaries.
In this atlas those double stars only are included the brighter component of which is
as bright as the sixth magnitude, and the other as bright as the ninth or tenth magnitude.
The list therefore contains those double stars which are seen as single stars with the naked
eye, but which may be seen as double with small-sized telescopes. These stars are marked
D upon the maps, this letter placed as a subscript to the letter or number designating the
star. If the star is without letter or number the D is placed in parenthesis.
The following table contains the most interesting double stars of those charted, com-
piled from various authorities, with the important facts regarding each. The list includes
those which surely form a binary system, and also those which are optically interesting
because of contrast of color between their components. The magnitudes of the components
are given and the position angle and distance of each pair. The position angle is reckoned
from the north point towards the east, the vertex of the angle at the brighter component.
The position angles and distances of the stars which are known to be revolving about their
common centre of gravity are subject to change ; the values given are necessarily approxi-
mate, but are sufficient for purposes of identification.
20
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24 EXPLANATORY TEXT.
USE OF THE STAR ATLAS.
The following suggestions are offered for the assistance of those using the atlas for
either constellation study or the examination of the sky with the telescope.
DESIGNATION OF STELLAR POSITIONS IN THE SKY.
The method used by astronomers for designating positions of the heavenly bodies
should be understood. This is precisely the same as that of designating positions on the
earth by their longitude and latitude. Upon the sky, which appears to us as a sphere, one
half of whose inner surface is always visible, we must imagine the equator to be drawn and
a system of meridians and parallels to be added. The celestial equator is the trace upon
the sky which the plane of the earth's equator would make. As we see it from any point
of the earth's surface except the poles, it passes through the east and west points of the
horizon, and is inclined to the horizon by an angle which is 90° minus the latitude of
the place. Where it crosses the meridian, it is distant from the zenith by an angle equal
to the latitude of the place. The sun in its daily path across the sky describes the equator
at the time of the equinoxes, about March 20th and September 21st ; on other days it
describes parallels either north or south of the equator.
The pole of the equator is the fixed point in the sky which marks the prolongation of
the earth's axis. It is always due north of the observer in the northern hemisphere or due
south in the southern hemisphere, and is as many degrees above the horizon as the latitude
of the place of observation. Its place is indicated roughly for northern observers by the
second magnitude star a Ursce Minoris, or Polaris, and for southern observers by the fifth
magnitude star <r Octantis. The great circles, all of which intersect at the pole and are
drawn perpendicular to the equator at its several points, like the meridians on the earth, are
called in the sky hour circles, not meridians. The term meridian is reserved for the circle
passing through the pole and the observer's zenith. Each hour circle in turn momentarily
coincides with the observer's meridian, as the earth turns on its axis. The parallels to the
celestial equator are drawn precisely as upon the earth. They are called parallels of decli-
nation instead of parallels of latitude. Each of the heavenly bodies describes the equator
or one of these parallels as the daily rotation of the earth on its axis causes it to move
across the sky. One of the best ways of fixing the whole system of circles in the mind is
to watch the movements of the heavenly bodies for a few hours on some clear night, having
first located the east and west points of the horizon and the position of the pole.
Each star in the sky has an hour circle passing through it, just as each point on the
earth is upon one of the terrestrial meridians. The distance of the star from the celestial
equator is called its declination, north or + if the star is north of the equator, and south or —
if south of the equator. This corresponds precisely with latitude on the earth. In order
to get the other measure corresponding with longitude, it is necessary to select one of the
hour circles as a reference circle, just as the meridian passing through Greenwich is chosen
on I lie earth. The hour circle passing through the point on the celestial equator where the
sun crosses it in the spring, called therefore the vernal equinox, is selected as the reference
hour circle. It is called the equinoctial cohere. The hour circle at right angles to this,
which therefore passes through the sun's solstitial points in summer and winter, is called the
solstitial colure. The angle between the equinoctial colure and the hour circle passing
through any star is called its right ascension. It corresponds with longitude on the earth,
USE OF THE STAB ATLAS. 25
with the exception that it is reckoned from the equinoctial colure towards the east all the
way around the sphere, amounting therefore to 24 hours or 360°, while longitude is
reckoned both eastward and westward from the meridian of Greenwich and therefore does
not exceed 12 hours or 180°. Right ascension is usually given in hours, minutes, and
seconds instead of degrees, minutes, and seconds, just as is frequently done in expressing
terrestrial longitudes.
It is a great help to a living appreciation of the system of circles above described and
their use in determining tlie right ascension and declination of the heavenly bodies, if one
will take the trouble to estimate the right ascension and declination of any star, and then
compare them with the true values given on the chart. To do this it is necessary first to
know where the vernal equinox is in the sky, or else the right ascension of some star which
can be used instead for reference. In the latter case the difference between the right as-
cension of the given star and the reference star is estimated, and this difference added to
the known right ascension. It is wise to select for these estimates stars in different parts
of the sky.
CONSTELLATION STUDY.
An acquaintance with the leading star groups is to be recommended not only for itself,
but because it gives a clearer idea of the motion of the earth on its axis and about the sun,
and also of lunar and planetary movements. It is well, however, to remember that the
tracing of the old figures is no part of modern Astronomy, and that little resemblance is to
be sought between the names of the constellations and the stars grouped within them. It
is very doubtful if the ancient astronomers who invented this method of designating star
groups fancied close resemblances between the groups and the names assigned. In only a
few cases, notably those of a snake-like figure, as Draco, Serpens, and Hydra, is it possible to
detect any resemblance whatever. It is also well to recall that the constellations occupy a
very humble position in the modern science of Asti'onomy, as their use is simply the giving
of names to areas in the sky.
The chief difficulties to be encountered in studying the constellations arise from their
changing positions in the sky due to the earth's daily motion on its axis and its annual
motion around the sun. As a result of the former, the same constellation appears tipped
at a different angle in one part of the sky than in another a few hours later. As a result
of the latter the constellations appear farther westward on any evening than they did at
the same time the previous evening. The remedy for these difficulties is to learn the con-
stellations with regard to each other and not with regard to the time of day or of year, and
certainly not with regard to terrestrial objects.
The following plan is suggested for a systematic study of the constellations :
1. Divide the heavens into four grand divisions, bounded by the equinoctial and
solstitial colures. Trace these colures in the sky by the prominent stars near which they
pass. In the northern sky the seven stars of Ursa Major known popularly as the Dipper
will furnish a beginning. The two stars a and ft, forming the side of the bowl of the
Dipper and known as the "pointers," will lead to the pole star, a Ursce Minoris, by pro-
longing the line from /3 to a to about five times its length. The middle star of the seven,
8 Ursce Majoris, at the junction of the handle with the bowl of the Dipper, and the faintest
star of the seven, is very near the equinoctial colure. Imagine a line connecting the pole
star with 8 Ursce Majoris. It is a portion of the equinoctial colure ; if prolonged from the
pole star beyond 8 Ursce Majoris it will intersect the equator at the autumnal equinox.
The star rj Virginis is not far from this point. If prolonged in the other direction from S
2G EXPLANATORY TEXT.
Ursce Majoris beyond the pole star it will intersect the equator at the vernal equinox.
There is a line of bright stars easily traced which marks the way, made up of /3 Cassiopeia,
a Andromeda}, and y Pegasi. The first of these is in the foot of the chair-shaped figure
which is the characteristic figure of Cassiopeia ; the second and third form the eastern side of
the conspicuous quadrilateral known as the " Square of Pegasus." The vernal equinox it-
self is in the relatively starless region south of y Pegasi ; the line from a Andromeda} to y
Pegasi should be prolonged as far beyond the latter as they are apart. After the equinoc-
tial colure has been traced as above, and the vernal and autumnal equinoxes located, the
solstitial colure may be similarly traced at right angles to the above. It will lead nearly to
17 Geminorum for the summer solstice, and in the reverse direction to /a Sagittarii for the
winter solstice.
2. Learn the zodiacal groups. Each of these has a characteristic figure, by which it
may be recognized. The groups are of first importance, because in them lies the ecliptic
or the sun's path through the heavens, and also the paths of the moon and leading planets.
It is advisable to note from the maps just where the ecliptic itself passes among the stars
of these groups.
•3. Add the leading constellations north and south of the zodiacal groups, and later
the less conspicuous groups. At first only the leading stars should be noted, the fainter
ones to be added later if desired.
4. Learn the twenty stars usually known as stars of the first magnitude.
The constellations are best learned by their characteristic figures. In order to aid in
this study, six smaller maps precede the main maps of the atlas. Their outlines and
general plan are precisely the same as those of the larger maps. They contain the stars
down to the fourth magnitude^ with a few fainter stars where necessary to complete a
characteristic figure. In many cases there is no question as to what constitutes the leading
stellar figure of any constellation area, but in others different observers may sometimes
differ as to the figures. The connecting lines which are drawn upon these maps are
intended as guides to help in tracing the characteristic figures. It is to be expected of
course that different students will oftentimes prefer different arrangements to those here
presented.
The student who is interested in the historical development of the subject may profit-
ably refer to the larger maps and note the outlines of the old figures hi their relation to the
actual stellar figures.
In order to facilitate the study of the constellations in an orderly way, a rearrange-
ment of the constellations according to the four divisions of the sky is here given. The
circumpolar constellations of all four divisions can best be studied together, but the equa-
torial constellations of the four divisions by themselves. For this reason, the maps of this
atlas are arranged as two circumpolar maps, and the intermediate parts of the sky in four
divisions bounded by the equinoctial and solstitial colures. The Roman numerals I, II,
III, and IV refer to the four divisions respectively. The zodiacal constellations are
printed in small capitals, and the other original constellations of Ptolemy's list, which
have the most conspicuous figures in the northern sky, in italics. Where a constellation
area is partly in one and partly in another division, it is here listed in the division in
which the greater part of its area lies.
USE OF THE STAR ATLAS.
27
Table IX. — Constellations arranged according to their Position in the Sky.
Northern Polar.
I.
II.
III.
IV.
Cassiopeia
Lynx
Ursa Minor
Cygnus
Camelopardalis
Ursa Major
Draco
Lacerta
Perseus
Cepheus
Equatorial I.
Equatorial II.
Equatorial III.
Equatorial IV.
Andromeda
Leo Minor
Coma Berenices
Lyra
Triangulum
Gemini
Canes Venatiei
Aquila
Auriga
Cancer
Bootes
Sat/itta
Pisces
Leo
Hercules
Vulpecula
Aries
Monoceros
Corona Borealis
Ih'lph inus
Taurus
Canis Minor
Ophiuchus
Equuleus
Cetus
Sextans
Serpens
Pegasus
Eridanus
Hydra
Virgo
Scutum
Orion
Crater
Libra
Sagittarius
Lepus
Canis Major
Scorpius
Capricornus
Sculptor
Argo (Puppis)
Corvus
Aquarius
Fornax
(Malus)
Lupus
Microscopium
Caelum
Antlia
Pise is Australis
Coluniba
Souther,
f Polar.
I.
II.
III.
IV.
Phoenix
Argo (Vela)
Centauries
Corona Australis
Horologium
(Carina)
Norma
Grus
Hydras
Volans
Ara
Telescopium
Reticulum
Cliamseleon
Crux
Indus
Dorado
Circinus
Tucana
Pictor
Musca
Pavo
Mensa
Triangulum Australe
Apus
Octans
The names of the months given at the margins of the star maps show the times of
year when the constellations can best be studied in the evening. The names are placed be-
neath the hour circles which correspond with the meridian at 9 p.m. local time. On the
circumpolar maps the names are placed under the hour circles which extend from the pole
downward to the horizon at the time named. To illustrate, — suppose that the heavens
are to be examined October 1st, 9 p.m. Map V shows that at that time the hour circle
which marks the right ascension, 21 h. 40 min., nearly coincides with the meridian.
The constellations west of the meridian are those west of this hour circle and are given on
Map V; those east of the meridian are partly on Map V and Map II. Map I shows how
the northern constellations appear to a person in the northern hemisphere when the page
is turned so that the date is at the bottom. Cass^eia is above the pole towards the right,
Ursa Major low in the sky below the pole. The following table is given to aid still
further in determining the position of the constellations at different times of the year. It
eives the riedit ascensions which coincide with the meridian at 9 p.m. on the dates named.
28
EXPLANATORY TEXT.
Table X. — Sidereal Time at 9 p.m., or Right Ascension of the Hour Circle
WHICH COINCIDES WITH THE MERIDIAN OF THE OBSERVER.
January 1
3 h. 45 m.
April
1
9h. 39 m.
July 1
15 k. 38 m.
October 1
21 h. 41 m,
15
4 40
15
10 34
15
16 33
15
22 36
February 1
5 47
May
1
11 37
August 1
17 40
November 1
23 43
15
6 42
15
12 33
15
IS 35
15
0 38
March 1
7 37
June
1
13 40
September 1
19 42
December 1
1 41
15
8 32
15
14 35
15
20 38
15
2 36
The maps giving the constellations near the equator, Maps II-V, are arranged with
the west toward the right and the east toward the left, just as the sky appears to a person
in the northern hemisphere when facing south. If the atlas is used in the southern hemi-
sphere, the page is to be inverted. The equator is drawn as a horizontal line ; it must be
remembered that in the sky it is a semicircle which extends from the eastern point of the
horizon to the western point, and that where it crosses the meridian it is distant from the
zenith by an amount equal to the observer's latitude. Therefore, if the map is held so that
the hour circle which is on the meridian is nearly vertical, the equator at both the left and
the right will gradually approach the horizon, touching it at hour circles six hours greater
and less than that on the meridian. If one views the constellations facing the east or
west, he may turn the atlas so that the equator as drawn will make an angle with the ver-
tical equal to the latitude of the place, and the star groups will appear at about the angle
which they have in that part of the sky.
TELESCOPIC STUDY.
The atlas is designed to assist those with small telescopes who may desire to find
objects in the sky. For this reason, in addition to the stars readily visible without a tele-
scope, the leading clusters, nebulae, double stars, red stars, and variables have been located
on the maps. The number of stars of the fainter magnitudes visible in a telescope of only
2 inches aperture is so large that they could not be charted without crowding the maps.
The stars charted can be seen with the naked eye and examined themselves, or used as
starting-points from which to find the other objects charted. The lists given in the
preceding pages contain the leading objects of each class in the sky.
It is well to know what can be expected of any given telescope. One of 2 inches
aperture will show stars as faint as the 10th magnitude ; of 4 inches aperture, as faint as
the 12th magnitude ; of 10 inches aperture, as faint as the 14th magnitude. But stars on
the extreme limit of brightness thus stated can be seen only when atmospheric conditions
are good and the instrument well focussed for the observer's eye. The dividing power of a
telescope in the examination of double stars depends upon the magnifying power used and
also upon the steadiness of the atmosphere and the magnitudes of the components. The
magnifying power of the telescope under ordinary atmospheric conditions is rarely more
than 20 or 30 times the aperture of the telescope in inches. Familiarity with the instru-
ment and its different eyepieces will show the observer what eyepieces are best adapted for
use under different conditions. Double stars, the distance of whose components is less than
2" or 3" are difficult objects for the amateur to divide with telescopes under 6 inches
aperture, especially if the components are bright. • The quadruple star e Lyrce is an excel-
lent object with which to test the capacity of the telescope for this kind of observing.
USE OF THE STAR ATLAS. 29
In order to use the star chart to find objects invisible to the naked eye, when the tele-
scope is not provided with setting circles, it is well to know the diameter of the field of
view in minutes of arc. This will differ for different eyepieces, diminishing as the magni-
fying power increases. It can be determined in several ways, as (1) by estimating the
diameter of the field in terms of the diameter of the moon seen with the given eyepiece.
The moon's diameter is about 32'. (2) By determining the time which it takes a star to
move centrally across the field, the telescope remaining at rest. If the star is near the
equator and the time is expressed in minutes and a fraction, simply multiplying by 15 will
give the diameter of the field in minutes of arc. If the star is not near the celestial equa-
tor, the resulting value will be too large and must be multiplied by the cosine of the star's
declination. When the diameter of the field is known, it is easy to move the telescope
from a star towards which the telescope may be directed a sufficient amount to bring the
desired object into the field. If the object, for instance a nebula, is on the star map, its
distance and direction from a star visible to the naked eye may be esthnated, and the
former converted into diameters of the field of the telescope. If an object not upon the
map is to be examined, for instance a comet, it may be located upon the map by its
right ascension and declination, and then its relation to some star determined.
Nebulce are usually disappointing objects in a small telescope. The descriptions pub-
lished describe them as they appear in very large instruments. Very few of them are suf-
ficiently bright to show much detail of structure unless the telescope is of at least 12 inches
aperture.
The colors of stars are usually not so marked in the telescope as one might expect.
The uncorrected color of the telescope itself and the color added by the atmosphere, espec-
ially if the star is near the horizon, give a spurious tint which must not be confounded with
the real color of the star. It is also very necessary for noting colors of the star that the
telescope should be well focussed. The stars marked red are usually of a less pronounced
shade of red than the word might seem to indicate.
In the use of a telescope too little attention is often given to the firmness of the sup-
port of the telescope and to a careful focussing for the individual e}Te of the observer. Care
in these matters will enable the observer to use the instrument to better advantage, and
experience will often show that its capabdities are much greater than at first supposed.
31
CHARACTERISTIC CONSTELLATION FIGURES.
MAP I
Right Ascension 0"-xxiv
Declination +40°-+9C£
LLATI
AROUND
NORTJi POLE.
Right Ascension 0''-Vl''
MAP II
Declination -4.0°— + 40"
Ca/ie/L 0~V
4-0 XXIII
Right Ascension Vl"1 — XIP
MAP III
Declination-40°-*40°
CANES
VENATICI
COMA
BERENICES//
Brighter Than I" Mag. • P1 Mag. • 2d Mag. • 3° Mag. ^"Mag. -5t"Mag.
RI&HT ASCENSION. X 1 1 h -XVIII'
MAP IV
DECUNATI0N.-40 -+40
RIGHT ASCENSION, XVIII - XXIV
MAP V
DECLINATION -40°- *40°
3RI&HTER Than h' Mac • b' Mag. •£^Ma& • 3" Mag. -4'- Mag. • 5'"Mag
34
RIGHT ASCENSION
DECLINATION
CONSTELLATIONS
abound south I
MAP I.
Right Ascension, Oh—XXIVh,
Declination,+M>' — r90"
CONSTELLATIONS
AROUND
NORTH POLE
SYMBOLS.
© brighter il„<„ 1st Mag
# 1st Mag,
& 271(1 '/rf;/.
■$■ ■■nl Mm/.
* 4th Mag,
* 5th Mag,
• Oth Mag
SYMBOLS.
o fainter than 6th Mug
« red.
v variable
•■ double
— Iim n/iirS
>& cluster
nebula
iinjiif Am-'-n.si'mi. Oh — VII*
map ti.
Dvrlhnitio,).-.',!'' h JO"
J .A. ]ST IT A. B VID E CL£l ZMZBBB.lJNTOAT'E JVC B E B.
0 brighter than 1st Mag. ttlst Mag. *:•«<( M„rj. & 3rd Mag. * ,11, M,„, + 6th Mag. • Cd -tf| fainter titan Gtlt Mag h ,;,/. 1 variable. a double — two stars. » cluster
S° XXIII
Right Ascension. 177*. AY/7?.
Derlinafitm— 40- h40"
40 20 -im 40 20 VIII *0 20 VII "O a0 VI
x, 3VE ^b, c b: ; if e b ir, xj .a. b, ^r
fl firig/ifer than 1st Mag, & 1st Hag. # 2d Mag. # 3d Mug. * 4th Mag. + 5th Mag. '• OthW fainter than Gth Mag. u red v variable, o double. — tiro stars. & cluster. ■ nebula.
Right Awt'ti*ion .XlIh—XVTIIh .
_MAPl^l
L>< el hint ion — 1,0- — \-jO
XIX
XYII1 4Q 80 XVII «p go XVI | 4Q y
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$ brighter than Itt Mag. Htltt Mag, #tndMag. fr 3rd Mag. He 4th Mag. + 5th Mag. • 6th Mag. „ fainter than Bth Mag. » red. t variable. •.double. (iot alars. 4tt clutter.
Right .lueniximi . X\Mll!li. XXIVIi.
MAP V.
Did '! mil inn— 40 [-.'//
go , XIX 49 .20 XVIII
BO -WII
4 brighter than 1st Mag. p 1st Mag. # Snd Mag. #- 3rd Mag. $ 4th Mag. + 5th Mag. • '■"• j'"J- ■> fainter than 6th Mag. u red. * variable. >■ double. two stars. ift cluate
CONSTELLATIONS
AROUND
SOUTH POLE
SYMBOLS.
$ brighter than 1st Mag.
* m Mag.
# -'ml Mag.
# 3rd Mag.
* -ith .Xing'.
+ 5th Mag.
- Oth Mag.
SYMBOLS.
o fainter titan 6th Mag.
a red.
* variable
>■ double
— two stars
-'.'■;: cluster
nebula
WELLESLEY COLLEGE LIBRARY
3 5002 03505 9059
Science fQB
65
U7
Upton
, Wins
low,
1853-
1914.
Star
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